public class PictureData
{
    public byte[] Data { get; set; }
}

using NPOI.XSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel.Extensions;

    /// <summary>
    /// 獲取excel中圖片數(shù)據(jù)
    /// </summary>
    /// <param name="path">文件路徑</param>
    /// <returns>list</returns>
 private List<PictureData> GetDTWithImg(string path)
    {
        using (FileStream file = new FileStream(path, FileMode.Open, FileAccess.Read))
        {
            IWorkbook workbook = null;
            ISheet sheet = null;

            workbook = WorkbookFactory.Create(file);
            sheet = workbook.GetSheet("Sheet1");
            if (sheet == null)
            {
                sheet = workbook.GetSheetAt(0);
            }

            // 獲取繪圖對象
            XSSFDrawing drawing = (XSSFDrawing)sheet.CreateDrawingPatriarch();
            List<XSSFPicture> picturesInColumnA = new List<XSSFPicture>();
            List<XSSFShape> shapes = drawing.GetShapes();
            foreach (XSSFShape shape in shapes)
            {
                if (shape is XSSFPicture)
                {
                    XSSFPicture picture = (XSSFPicture)shape;
                    XSSFClientAnchor anchor = (XSSFClientAnchor)picture.GetPreferredSize();                  
                    picturesInColumnA.Add(picture);
                }
            }
            List<PictureData> pictureDataList = new List<PictureData>();
            //將圖片數(shù)據(jù)放到集合中
            foreach (XSSFPicture picture in picturesInColumnA)
            {
                byte[] pictureData = picture.PictureData.Data;
                PictureData data = new PictureData
                {                   
                    Data = pictureData
                };
                pictureDataList.Add(data);
            }
            return pictureDataList;
        }

    }